package com.fengjue.config.security;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.security.core.userdetails.UserDetailsService;
import org.springframework.security.web.authentication.WebAuthenticationDetailsSource;
import org.springframework.web.filter.OncePerRequestFilter;

import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * JWT登录授权过滤器
 */
public class JwtAuthencationTokenFilter extends OncePerRequestFilter {

    @Value("${jwt.tokenHeader}")
    private String tokenHeader;

    @Value("${jwt.tokenHead}")
    private String tokenHead;

    @Autowired
    private JwtTokenUtil jwtTokenUtil;

    @Autowired
    private UserDetailsService userDetailsService;

    @Override
    protected void doFilterInternal(HttpServletRequest request,
                                    HttpServletResponse response,
                                    FilterChain filterChain)
            throws ServletException, IOException {

        String authHeader = request.getHeader(tokenHeader);
        System.out.println("authHeader = " + authHeader);
        // 存在token ，通过tokenHeader获取头部信息,看value是不是以tokenHead开头
        if (null != authHeader && authHeader.startsWith(tokenHead)) {
            String authToken = authHeader.substring(tokenHead.length());
            String username = jwtTokenUtil.getUserNameFromToken(authToken);
            System.out.println("username = " + username);
            // token 存在用户名，但是未登录
            if (null != username && null == SecurityContextHolder.getContext().getAuthentication()) {
                // 登录
                UserDetails userDetails = userDetailsService.loadUserByUsername(username);
                // 判断token是否有效，重新设置到用户对象
                if (jwtTokenUtil.validateToken(authToken, userDetails)) {
                    UsernamePasswordAuthenticationToken authenticationToken = new UsernamePasswordAuthenticationToken(
                            userDetails,
                            null,
                            userDetails.getAuthorities()
                    );


                    authenticationToken.setDetails(new WebAuthenticationDetailsSource().buildDetails(request));
                    // 设置全局权限
                    SecurityContextHolder.getContext().setAuthentication(authenticationToken);
                }
            }

        }

        filterChain.doFilter(request, response);
    }
}
